Thermal management system and method for a vehicle propulsion system

Abstract

A vehicle propulsion system includes an engine having a coolant inlet and a coolant outlet, a coolant pump having an outlet in communication with the engine coolant inlet, a pressure sensor in fluid communication with the engine coolant outlet and that generates a pressure signal indicative of a pressure in the engine coolant outlet, and a controller in communication with the pressure sensor and the coolant pump. The controller is programmed to control a flow of coolant through the engine from the coolant pump based upon the pressure signal.

What is claimed is: 
     
       1. A thermal management system for a vehicle propulsion system, the system comprising:
 an engine having a coolant inlet and a coolant outlet; 
 a coolant pump having an outlet in communication with the engine coolant inlet; 
 a pressure sensor in fluid communication with the engine coolant outlet and that generates a pressure signal indicative of a pressure in the engine coolant outlet; 
 a controller in communication with the pressure sensor and the coolant pump, wherein the controller is programmed to control a flow of coolant through the engine from the coolant pump based upon the pressure signal; 
 a second valve having a coolant inlet in communication with the engine coolant outlet and a plurality of coolant outlets; 
 a second heat exchanger having a coolant inlet in communication with a first of the plurality of valve coolant outlets and a coolant outlet in communication with the pump coolant inlet; 
 a third heat exchanger having a coolant inlet in communication with a second of the plurality of valve coolant outlets and a coolant outlet in communication with the pump coolant inlet; and 
 a bypass fluid conduit having a coolant inlet in communication with a third of the plurality of valve coolant outlets and a coolant outlet in communication with the pump coolant inlet, wherein the controller is further programmed to 
 determine a first potential benefit based upon a loss function of the second heat exchanger; 
 determine a second potential benefit based upon a loss function of the third heat exchanger; 
 compare the first potential to the second potential; and 
 operate at least one of the first valve and the second valve to proportionally distribute coolant flow between the first heat exchanger, the second heat exchanger, the third heat exchanger, and the bypass fluid conduit based upon a result of the comparison. 
 
     
     
       2. The system of  claim 1 , further comprising an engine coolant outlet temperature sensor that provides an engine coolant outlet temperature signal to the controller. 
     
     
       3. The system of  claim 2 , further comprising a transmission fluid temperature sensor that provides a transmission fluid temperature signal to the controller, wherein the controller determines the first potential further based upon the engine coolant outlet temperature signal and the transmission fluid temperature signal.